System for providing blood glucose measurements to an infusion device

ABSTRACT

An infusion system includes an infusion device and a sensing device. The infusion system may further include a characteristic determining device. The infusion device also includes a communication system for transmitting to and receiving communications from the sensing device or a computer. The sensing device may sense an analyte of a bodily fluid of the user. The analyte may be calibrated using data from the infusion device and from a characteristic determining device. The system may be set up to automatically call for assistance when analytes reach a certain level.

RELATED APPLICATION DATA

This application is a continuation of U.S. patent application Ser. No.10/867,529, filed Jun. 14, 2004, now U.S. Pat. No. 8,512,276, which is acontinuation-in-part of U.S. patent application Ser. No. 10/624,389,filed Jul. 22, 2003, now abandoned, which claims priority from U.S.Provisional Patent Application Nos. 60/398,199, filed Jul. 24, 2002, and60/412,998, filed Sep. 23, 2002, and also claims priority from U.S.Provisional Patent Application No. 60/478,697, filed Jun. 13, 2003, allof which are herein incorporated by reference in their entirety.

FIELD OF THE INVENTION

This invention relates generally to infusion systems that are used forinfusing a fluid into a user, and in particular, to apparatuses andmethods for providing blood glucose measurements to an infusion device.

BACKGROUND OF THE INVENTION

Patients with Type I diabetes and some patients with Type 2 diabetes useinsulin to control their blood glucose (BG) level. Typically, if apatient's BG level is too high, the patient can inject a “bolus” (dose)of insulin to lower his/her BG level from its present level to a desiredtarget level. Furthermore, patients may inject a bolus of insulin inanticipation of ingesting carbohydrates, thus heading off a sharp risein their BG level. Patients employ various calculations to determine theamount of insulin to inject. Bolus estimation software is available forcalculating an insulin bolus. Patients may use these software programson an electronic computing device, such as a computer, the Internet, apersonal digital assistant (PDA), or an insulin delivery device. Insulindelivery devices include infusion pumps, injection pens, and IV meters.The best bolus estimation software takes into account the patient'spresent BG level. Presently, a patient must measure his/her bloodglucose using a BG measurement device, such as a test strip meter(“meter”), a continuous glucose measurement system, a hospital hemacue,or an automated intermittent blood glucose measurement system. BGmeasurement devices use various methods to measure the BG level of apatient, such as a sample of the patient's blood, a sensor in contactwith a bodily fluid, an optical sensor, an enzymatic sensor, or afluorescent sensor. When the BG measurement device has generated a BGmeasurement, the measurement is displayed on the BG measurement device.Then the patient may visually read the BG measurement and physicallyenter the BG measurement into an electronic computing device tocalculate a bolus estimate. Finally, once the bolus estimate iscalculated, the patient must inject the insulin bolus or program aninsulin delivery device to deliver the bolus into their body.Unfortunately, this process is cumbersome and is subject to transcribingerrors—for example, the patient may not accurately enter the BGmeasurement that is displayed on the BG measurement device into theelectronic computing device. Thus, if the BG measurement is not enteredcorrectly, the bolus estimate is not accurate. Furthermore, once thebolus estimation is complete, the patient may not accurately enter thebolus amount into a programmable infusion device, or the patient mayread the bolus amount incorrectly and inject the wrong amount ofinsulin.

SUMMARY

In preferred embodiments of the present invention, an infusion systemfor infusing a fluid into a body of a user includes a characteristicdetermining device and an infusion device. The characteristicdetermining device includes a housing adapted to be carried by the user,a receptacle coupled to the housing for receiving and testing an analytefrom the user to determine a concentration of the analyte in the user, aprocessor contained in the housing and coupled to the receptacle forprocessing the determined concentration of the analyte from thereceptacle, and a communication system contained in the housing andcoupled to the processor for transmitting a communication including dataindicative of the determined concentration of the analyte in the user.In particular embodiments, the characteristic determining device mayalso include a lancing device coupled to the receptacle for obtainingthe analyte from the user. In preferred embodiments, the infusion deviceincludes a housing adapted to be carried by the user, a drive mechanismcontained in the housing and operatively coupled with a reservoircontaining the fluid for infusing the fluid into the body of the user, acommunication system contained in the housing for receiving thecommunication including the data indicative of the determinedconcentration of the analyte in the user from the determining device,and a processor contained in the housing and coupled to thecommunication system for processing the data indicative of thedetermined concentration of the analyte in the user and controlling theinfusion device. The infusion device further includes a bolus estimatorused in conjunction with the processor for calculating an estimatedamount of fluid to be infused into the body of the user based upon thereceived data indicative of the determined concentration of the analytein the user and a target concentration of the analyte in the user, andan indicator to indicate when the estimated amount of fluid to beinfused has been calculated. Additionally, the infusion device mayinclude a user input device for inputting an estimate of a material tobe ingested by the user, and the bolus estimator may include thecapability to calculate the estimated amount of fluid to be infused intothe body of the user based upon the inputted estimate of the material tobe ingested by the user. The infusion device may also include a memoryfor storing the data indicative of the determined concentration of theanalyte in the user received by the infusion device communication systemfrom the determining device communication system.

In particular embodiments, the characteristic determining deviceautomatically transmits the communication including the data indicativeof the determined concentration of the analyte in the user to theinfusion device. In other particular embodiments, the characteristicdetermining device further includes a user input device for inputtingcommands, and transmits the communication including the data indicativeof the determined concentration of the analyte in the user to theinfusion device in response to a command from the user input device. Inadditional embodiments, the characteristic determining device furtherincludes an indicator to indicate a status of the communicationincluding the data indicative of the determined concentration of theanalyte in the user being transmitted from the determining devicecommunication system to the infusion device communication system.

In some embodiments, the communication transmitted from thecharacteristic determining device to the infusion device furtherincludes a time at which the concentration of the analyte in the userwas determined. In additional embodiments, the processor of thecharacteristic determining device determines an amount of time that haselapsed since the concentration of the analyte in the user wasdetermined, and the communication transmitted from the determiningdevice to the infusion device further includes the elapsed amount oftime. Further, the processor of the characteristic determining devicemay cause the communication system of the characteristic determiningdevice not to transmit the communication including the data indicativeof the determined concentration of the analyte in the user if theelapsed amount of time exceeds a predetermined amount of time. In otherembodiments, the infusion device processor determines an amount of timethat has elapsed since the data indicative of the determinedconcentration of the analyte in the user was received, and causes thebolus estimator not to calculate the estimated amount of fluid to beinfused based upon the determined concentration of the analyte if theelapsed amount of time exceeds a predetermined amount of time. In stillother embodiments, the processor of the infusion device determines anamount of time that has elapsed since the concentration of the analytein the user was determined, and causes the bolus estimator not tocalculate the estimated amount of fluid to be infused based upon thedetermined concentration of the analyte if the elapsed amount of timeexceeds a predetermined amount of time.

In further embodiments, the determining device communication system iscapable of being deactivated and reactivated. The characteristicdetermining device includes a user input device for inputting commands,and the communication system of the characteristic determining device iscapable of being deactivated in response to a first command from theuser input device and being reactivated in response to a second commandfrom the user input device. Alternatively, the communication system ofthe characteristic determining device may be automatically reactivatedafter a predetermined amount of time has elapsed or at a predeterminedtime of day. Additionally, the characteristic determining device mayinclude a memory for storing data indicative of the determinedconcentration of the analyte in the user that is determined when thedetermining device communication system is deactivated, and thedetermining device communication system may transmit a communicationincluding the stored data to the infusion device communication systemwhen the determining device communication system is reactivated.

In still other embodiments, the processor of the characteristicdetermining device has unique identification information, and thecommunication transmitted from the characteristic determining device tothe infusion device further includes the unique identificationinformation of the determining device processor such that the infusiondevice is capable of discerning whether the communication is intendedfor receipt by the infusion device. In yet other embodiments, theprocessor of the infusion device has unique identification information,and the communication transmitted from the characteristic determiningdevice to the infusion device further includes the unique identificationinformation of the infusion device processor such that the infusiondevice is capable of discerning whether the communication is intendedfor receipt by the infusion device.

In preferred embodiments, the processor of the infusion device usespower cycling whereby power is periodically supplied to thecommunication system of the infusion device until a communication isreceived from the characteristic determining device. When acommunication is received from the characteristic determining device,the processor of the infusion device discontinues using power cyclingwhereby the power is continuously supplied to the infusion devicecommunication system. The infusion device processor may then resumeusing power cycling upon completing the receipt of the communicationincluding the data indicative of the determined concentration of theanalyte in the user from the determining device communication system.

In particular embodiments, the infusion system further includes aconnector for coupling the characteristic determining device to acomputer and downloading data from the characteristic determining deviceto the computer. The communication system of the infusion device isfurther capable of transmitting a communication including infusiondevice data to be downloaded, and the communication system of thecharacteristic determining device is further capable of receiving thecommunication including the infusion device data to be downloaded fromthe infusion device. The received infusion device data is thendownloaded from the characteristic determining device through theconnector to the computer. Alternatively, the characteristic determiningdevice may further include a memory for storing data, and the receivedinfusion device data may be stored in the memory of the characteristicdetermining device for subsequent downloading through the connector tothe computer.

In other particular embodiments, the characteristic determining devicefurther includes a user input device for inputting remote controlcommands for controlling the infusion device. The communication systemof the characteristic determining device further transmits acommunication including the remote control commands, and thecommunication system of the infusion device further receives thecommunication including the remote control commands from thecharacteristic determining device. The processor of the infusion devicethen controls the infusion device in accordance with the received remotecontrol commands.

In yet other particular embodiments, the infusion device furtherincludes a user input device for inputting remote control commands forcontrolling the characteristic determining device. The communicationsystem of the infusion device further transmits a communicationincluding the remote control commands, and the communication system ofthe characteristic determining device further receives the communicationincluding the remote control commands from the infusion device. Theprocessor of the characteristic determining device then controls thecharacteristic determining device in accordance with the received remotecontrol commands.

In additional embodiments, the characteristic determining device furtherincludes a determining device clock, and the infusion device furtherincludes an infusion device clock. The infusion device communicationsystem further transmits a communication including a time of theinfusion device clock, and the determining device communication systemfurther receives the communication including the time of the infusiondevice clock from the infusion device communication system. Thedetermining device clock is then set to the received time of theinfusion device clock. Alternatively, the determining devicecommunication system further transmits a communication including a timeof the determining device clock, and the infusion device communicationsystem further receives the communication including the time of thedetermining device clock from the determining device communicationsystem. The infusion device clock is then set to the received time ofthe determining device clock.

In accordance with another embodiment of the present invention, aninfusion device infuses a fluid into a body of a user and is capable ofcommunicating with a characteristic determining device, which is adaptedfor determining a concentration of an analyte in the user. The infusiondevice includes a housing adapted to be carried by the user, a drivemechanism contained in the housing and operatively coupled with areservoir containing the fluid for infusing the fluid into the body ofthe user, a communication system contained in the housing for receivinga communication including data indicative of the determinedconcentration of the analyte in the user from the characteristicdetermining device, and a processor contained in the housing and coupledto the communication system for processing the data indicative of thedetermined concentration of the analyte in the user and controlling theinfusion device. The infusion device also includes a bolus estimatorused in conjunction with the processor for calculating an estimatedamount of fluid to be infused into the body of the user based upon thereceived data indicative of the determined concentration of the analytein the user and a target concentration of the analyte in the user. Theinfusion device further includes an indicator to indicate when theestimated amount of fluid to be infused has been calculated.

In accordance with still another embodiment of the present invention, acharacteristic determining device determines a concentration of ananalyte in a body of a user and is capable of communicating with aninfusion device, which is adapted for infusing a fluid into the body ofthe user and calculating an estimated amount of the fluid to be infusedinto the body of the user based upon the determined concentration of theanalyte in the user and a target concentration of the analyte in theuser. The characteristic determining device includes a housing adaptedto be carried by the user, a receptacle coupled to the housing forreceiving and testing an analyte from the user to determine theconcentration of the analyte in the user, a processor contained in thehousing and coupled to the receptacle for processing the determinedconcentration of the analyte from the receptacle, and a communicationsystem contained in the housing and coupled to the processor fortransmitting a communication including data indicative of the determinedconcentration of the analyte in the user to the infusion device.

According to yet another embodiment of the present invention, aninfusion system includes a characteristic determining device and aninfusion device, and a method for infusing a fluid into a body of a useris provided. The method includes the steps of receiving and testing ananalyte from the user to determine a concentration of the analyte in theuser, transmitting with the characteristic determining device acommunication including data indicative of the determined concentrationof the analyte in the user, and receiving with the infusion device thecommunication including the data indicative of the determinedconcentration of the analyte in the user. The data indicative of thedetermined concentration of the analyte in the user received by theinfusion device from the characteristic determining device may then bestored in a memory of the infusion device. The method further includesthe steps of calculating an estimated amount of fluid to be infused intothe body of the user based upon the received data indicative of thedetermined concentration of the analyte in the user and a targetconcentration of the analyte in the user, and indicating when theestimated amount of fluid to be infused has been calculated.Additionally, the method may include the step of inputting an estimateof a material to be ingested by the user, and the estimated amount offluid to be infused into the body of the user is calculated furtherbased upon the inputted estimate of the material to be ingested by theuser.

In some embodiments, the communication including the data indicative ofthe determined concentration of the analyte in the user is automaticallytransmitted from the characteristic determining device to the infusiondevice. In other embodiments, the communication including the dataindicative of the determined concentration of the analyte in the user istransmitted from the characteristic determining device to the infusiondevice in response to an inputted command. In still other embodiments,the system indicates a status of the communication including the dataindicative of the determined concentration of the analyte in the userbeing transmitted from the characteristic determining device to theinfusion device.

In particular embodiments, the communication including the dataindicative of the determined concentration of the analyte in the usertransmitted from the characteristic determining device to the infusiondevice further includes a time at which the concentration of the analytein the user was determined. In other particular embodiments, the systemalso determines an amount of time that has elapsed since theconcentration of the analyte in the user was determined. In yet otherparticular embodiments, the system determines an amount of time that haselapsed since the communication including the data indicative of thedetermined concentration of the analyte in the user was received by theinfusion device.

In additional embodiments, the method further includes the steps oftransmitting with the infusion device a communication including a clocktime of the infusion device, receiving with the characteristicdetermining device the communication including the clock time of theinfusion device, and setting a clock time of the characteristicdetermining device to the received clock time of the infusion device.Alternatively, the method may include the steps of transmitting with thecharacteristic determining device a communication including a clock timeof the characteristic determining device, receiving with the infusiondevice the communication including the clock time of the characteristicdetermining device, and setting a clock time of the infusion device tothe received clock time of the characteristic determining device.

In accordance with a further embodiment of the present invention, aninfusion system for infusing a fluid into a body of a user includes acharacteristic determining device and an infusion device. Thecharacteristic determining device includes a determining device housingadapted to be carried by the user, a sensor coupled to the determiningdevice housing for determining a concentration of an analyte in theuser, a determining device processor contained in the determining devicehousing and coupled to the sensor for processing the determinedconcentration of the analyte from the sensor, and a determining devicecommunication system contained in the determining device housing andcoupled to the determining device processor for transmitting acommunication including data indicative of the determined concentrationof the analyte in the user. The infusion device includes an infusiondevice housing adapted to be carried by the user, a drive mechanismcontained in the infusion device housing and operatively coupled with areservoir containing the fluid for infusing the fluid into the body ofthe user, an infusion device communication system contained in theinfusion device housing for receiving the communication including thedata indicative of the determined concentration of the analyte in theuser from the determining device communication system, and an infusiondevice processor contained in the infusion device housing and coupled tothe infusion device communication system for processing the dataindicative of the determined concentration of the analyte in the userand controlling the infusion device.

In particular embodiments, the determining device communication systemautomatically transmits the communication including the data indicativeof the determined concentration of the analyte in the user to theinfusion device communication system. In other particular embodiments,the characteristic determining device further includes a user inputdevice for inputting commands, and the determining device communicationsystem transmits the communication including the data indicative of thedetermined concentration of the analyte in the user to the infusiondevice communication system in response to a command from the user inputdevice. In further particular embodiments, the characteristicdetermining device includes an indicator to indicate a status of thecommunication including the data indicative of the determinedconcentration of the analyte in the user being transmitted from thedetermining device communication system to the infusion devicecommunication system.

In some embodiments, the infusion device further includes a bolusestimator used in conjunction with the infusion device processor forcalculating an estimated amount of fluid to be infused into the body ofthe user based upon the received data indicative of the determinedconcentration of the analyte in the user and a target concentration ofthe analyte in the user. The infusion device also includes an infusiondevice indicator to indicate when the estimated amount of fluid to beinfused has been calculated. In other embodiments, the infusion devicefurther includes a memory for storing data, and the data indicative ofthe determined concentration of the analyte in the user received by theinfusion device communication system from the determining devicecommunication system is stored in the memory of the infusion device.

In additional embodiments, the determining device processor has uniqueidentification information, and the communication transmitted from thedetermining device communication system to the infusion devicecommunication system further includes the unique identificationinformation of the determining device processor such that the infusiondevice is capable of discerning whether the communication is intendedfor receipt by the infusion device. In yet additional embodiments, theinfusion device processor has unique identification information, and thecommunication transmitted from the determining device communicationsystem to the infusion device communication system further includes theunique identification information of the infusion device processor suchthat the infusion device is capable of discerning whether thecommunication is intended for receipt by the infusion device.

In further embodiments, the determining device communication system iscapable of being deactivated and reactivated. The characteristicdetermining device may also include a memory for storing data indicativeof the determined concentration of the analyte in the user that isdetermined when the determining device communication system isdeactivated. The determining device communication system then transmitsa communication including the stored data to the infusion devicecommunication system when the determining device communication system isreactivated.

In still further embodiments, the infusion device processor uses powercycling whereby power is periodically supplied to the infusion devicecommunication system until a communication is received from thedetermining device communication system. The infusion device processordiscontinues using power cycling whereby the power is continuouslysupplied to the infusion device communication system when thecommunication including the data indicative of the determinedconcentration of the analyte in the user is received from thedetermining device communication system. Further, the infusion deviceprocessor resumes using power cycling upon completing the receipt of thecommunication including the data indicative of the determinedconcentration of the analyte in the user from the determining devicecommunication system.

In other embodiments, the infusion system further includes a connectorfor coupling the characteristic determining device to a computer anddownloading data from the characteristic determining device to thecomputer. The infusion device communication system is further capable oftransmitting a communication including infusion device data to bedownloaded, and the determining device communication system is furthercapable of receiving the communication including the infusion devicedata to be downloaded from the infusion device communication system. Thereceived infusion device data is then downloaded from the characteristicdetermining device through the connector to the computer. The downloadmay be transparent to the user. The download may occur whenever thecomputer senses the presence of the infusion device or characteristicdetermining device, when the infusion device or characteristicdetermining device is placed in a cradle, and/or at certain,predetermined times. The download may be a partial download. In furtherembodiments, the computer and/or several devices are configured to shareinformation with each other.

In yet other embodiments, the characteristic determining device furtherincludes a determining device clock, and the infusion device furtherincludes an infusion device clock. The infusion device communicationsystem further transmits a communication including a time of theinfusion device clock, and the determining device communication systemfurther receives the communication including the time of the infusiondevice clock from the infusion device communication system. Thedetermining device clock is then set to the received time of theinfusion device clock. Alternatively, the determining devicecommunication system further transmits a communication including a timeof the determining device clock, and the infusion device communicationsystem further receives the communication including the time of thedetermining device clock from the determining device communicationsystem. The infusion device clock is then set to the received time ofthe determining device clock.

In yet further embodiments, the infusion system comprises an infusiondevice and a sensing device. The sensing device includes a sensor and atransmitter in communication with the infusion device. The sensingdevice may sense an analyte of a bodily fluid of the user. The sensingdevice may be calibrated using data from the infusion device and/or froma characteristic determining device. In further embodiments, the sensingdevice senses additional physiological characteristics. In still furtherembodiments, the system is set up to automatically call for assistancewhen analytes reach a certain level. The call may include a globalpositioning system (GPS) location.

BRIEF DESCRIPTION OF THE DRAWINGS

A detailed description of embodiments of the invention will be made withreference to the accompanying drawings, wherein like numerals designatecorresponding parts in the several figures.

FIG. 1 is a perspective view of a blood glucose meter and an infusionpump in accordance with an embodiment of the present invention.

FIG. 2 is a simplified block diagram of an infusion pump in accordancewith an embodiment of the present invention.

FIG. 3(a) is a block diagram of an RF communication system in theinfusion pump in accordance with an embodiment of the present invention.

FIG. 3(b) is a block diagram of an RF communication system in theinfusion pump in accordance with another embodiment of the presentinvention.

FIG. 4(a) is a simplified block diagram of a blood glucose meter inaccordance with an embodiment of the present invention.

FIG. 4(b) is a simplified block diagram of a blood glucose meter inaccordance with another embodiment of the present invention.

FIG. 5 is a simplified block diagram of a blood glucose meter inaccordance with still another embodiment of the present invention.

FIG. 6 is a perspective view of a sensing device in accordance with anembodiment of the present invention.

FIG. 7 is a perspective view of a sensing device in accordance with anembodiment of the present invention.

DETAILED DESCRIPTION

As shown in the drawings for purposes of illustration, the invention isembodied in a system for communicating blood glucose measurements from ablood glucose measurement device to an electronic computing device,which utilizes the blood glucose measurements to calculate a bolusestimate. In preferred embodiments, the blood glucose (BG) measurementdevice is a blood glucose (BG) test strip meter, and the electroniccomputing device is an insulin delivery device, preferably an externalinsulin infusion pump. The BG meter utilizes a test strip with a sampleof the user's blood to measure the user's BG level, and then transmitsthe BG measurement to the infusion pump using a communication systemthat includes, for example, a radio frequency (RF) transmitter ortransceiver. The infusion pump receives the BG measurement from the BGmeter, and includes bolus estimation software to calculate a bolusestimate using the received BG measurement. The infusion pump may thendeliver a bolus amount to the user based on the calculated bolusestimate. Transmission of the BG measurement from the BG meter to theinfusion pump eliminates user transcription errors (i.e., the user maynot accurately enter the BG measurement into the infusion pump) andsimplifies the use of a bolus estimator. In particular embodiments, theBG meter may also function as a remote controller for the infusion pump,so the user can initiate a bolus delivery (without the bolus estimator)or stop a bolus delivery using buttons located on the BG meter. The BGmeter may further function as a communications link for downloading datafrom the infusion pump to a computer or the like.

However, in alternative embodiments of the present invention, the BGmeasurement device may be a continuous glucose measurement system, ahospital hemacue, an automated intermittent blood glucose measurementsystem, and the like, and/or the BG measurement device may use othermethods for measuring the user's BG level, such as a sensing deviceincluding a sensor in contact with a body fluid, an optical sensor, anenzymatic sensor, a fluorescent sensor, a blood sample placed in areceptacle, or the like.

In further alternative embodiments, the electronic computing device maybe another type of insulin delivery device, such as an implantableinsulin infusion pump or system that uses a combination of implantableand external components, an injection pen, an IV meter, and the like. Inother alternative embodiments, the electronic computing device may be acomputer, the Internet, a personal digital assistant (PDA), a portabletelephone, a custom computing device, and the like. In still furtheralternative embodiments, the BG measurement device may use samples frombody fluids other than blood, such as interstitial fluid, spinal fluid,saliva, urine, tears, sweat, or the like. In yet other alternativeembodiments, other measurement devices may be utilized to determine theconcentrations, levels, or quantities of other characteristics,analytes, or agents in the user, such as hormones, cholesterol, oxygen,pH, lactate, heart rate, respiratory rate, medication concentrations,viral loads (e.g., HIV), or the like. In still other alternativeembodiments, other fluids may be delivered to the user, such asmedication other than insulin (e.g., HIV drugs, drugs to treat pulmonaryhypertension, iron chelation drugs, pain medications, and anti-cancertreatments), chemicals, enzymes, antigens, hormones, vitamins, or thelike. Particular embodiments are directed towards the use in humans;however, in alternative embodiments, the infusion devices may be used inanimals.

In addition to, or in lieu of, the BG measurement device such as the BGmeter, the present invention may include a sensing device, which sensesanalyte values. In preferred embodiments, the analyte values are BGvalues. The sensing device preferably includes a sensor in contact witha bodily fluid of the user and a transmitter, wired and/or wireless. TheBG sensor data are transmitted to the electronic computing device, forexample an insulin delivery device, preferably an external insulininfusion pump. BG measurement values from the BG measurement device,such as the BG meter, are also sent to the electronic computing device.The sensor data is calibrated using the BG measurement values, and thecalibrated sensor data and/or BG measurement values are shown on adisplay of the electronic computing device. In still furtherembodiments, the sensor is incorporated into the electronic computingdevice. The electronic computing device may transmit sensor data to theBG measurement device and/or the sensor data may be used in theelectronic computing device. The sensor data is calibrated using BGmeasurement values from the BG meter, which may be transmitted to theelectronic computing device and/or entered into the electronic computingdevice manually. The calibrated sensor data and/or BG measurement valuesmay then be displayed on the display of the electronic computing device.

In preferred embodiments of the present invention, a blood glucose (BG)measurement device measures a user's BG level and then communicates theBG measurement to an electronic computing device, which utilizes the BGmeasurement to calculate a bolus estimate. In the embodiment illustratedin FIG. 1, the BG measurement device is a BG test strip meter 10, andthe electronic computing device is an insulin delivery device,preferably an external insulin infusion pump 50.

Referring to FIGS. 1 and 4(a), a housing 13 of the BG meter 10preferably includes a test strip receptacle or port 11 for receiving andanalyzing a test strip 12 or the like with a sample of the user's blood14 on the test strip 12 to obtain a BG measurement. The BG meter 10 isadapted to be carried by the user, for example, in the hand, on thebody, in a clothing pocket, attached to clothing (e.g., using a clip,strap, adhesive, or fastener), and the like. In particular embodiments,the user may utilize a separate lancing device (not shown) to obtain ablood sample, and then apply the sample onto the test strip 12. In otherparticular embodiments, the BG meter 10 may incorporate a lancing device(not shown) that obtains and automatically applies the blood sample ontothe test strip 12.

In alternative embodiments, the BG measurement device may be acontinuous glucose measurement system, a hospital hemacue, an automatedintermittent blood glucose measurement system, and the like, and/or theBG measurement device may use other methods for measuring the user's BGlevel, such as a sensor in contact with a body fluid, an optical sensor,an enzymatic sensor, a fluorescent sensor, a blood sample placed in areceptacle, or the like. The BG measurement device may generally be ofthe type and/or include features disclosed in U.S. patent applicationSer. No. 09/377,472 filed Aug. 19, 1999 and entitled “TelemeteredCharacteristic Monitor System and Method of Using the Same,” Ser. No.09/334,996 filed Jun. 17, 1999 and entitled “Characteristic Monitor witha Characteristic Meter and Method of Using the Same,” Ser. No.09/487,423 filed Jan. 20, 2000 and entitled “Handheld Personal DataAssistant (PDA) with a Medical Device and Method of Using the Same,” andSer. No. 09/935,827 filed Aug. 23, 2001 and entitled “Handheld PersonalData Assistant (PDA) with a Medical Device and Method of Using theSame,” which are herein incorporated by reference. Such BG measurementdevices may be adapted to be carried by the user, for example, in thehand, on the body, in a clothing pocket, attached to clothing (e.g.,using a clip, strap, adhesive, or fastener), and the like. In furtheralternative embodiments, the BG measurement device may use samples frombody fluids other than blood, such as interstitial fluid, spinal fluid,saliva, urine, tears, sweat, or the like. In yet other alternativeembodiments, other characteristic determining or measuring devices maybe utilized to determine or measure the concentrations, levels, orquantities of other characteristics, analytes, or agents in the user,such as hormones, cholesterol, oxygen, pH, lactate, heart rate,respiratory rate, medication concentrations, viral loads (e.g., HIV), orthe like.

In particular embodiments, once the BG meter 10 obtains a BGmeasurement, the BG measurement is transmitted to the infusion pump 50using a communication system, which includes a radio frequency (RF)transmitter 15, as will be described below. In other particularembodiments, the RF transmitter 15 may be replaced with an RFtransceiver 19 (as shown in FIG. 4(b)) or 36 (as shown in FIG. 5), andthe BG measurement may be transmitted to the infusion pump 50 using theRF transceiver 19 or 36.

The test strip port 11 and RF transmitter 15 are coupled to a processor17 contained in the housing 13 of the BG meter 10. The processor 17 runsprograms and controls the BG meter 10, and is also connected to a memory30 for storing programs, history data, user defined information andparameters, and the like. The BG meter 10 also preferably includes adisplay 16 for providing the BG measurement and/or messages, such asstatus or error messages, to the user. In particular embodiments, thedisplay 16 may include a backlight for reading the display 16 in thedark.

In preferred embodiments, the BG meter 10 includes one or more buttons18 and 20 for operation of the meter 10, such as turning on/off themeter 10, reviewing previous BG measurements, transmitting BGmeasurements to the infusion pump 50, turning off the transmitter 15 (ortransceiver 19 (shown in FIG. 4(b)) or 36 (shown in FIG. 5)) in the BGmeter 10 so that it does not send a BG measurement to the infusion pump50, and the like. The BG meter 10 may further include a keypad 28 withone or more buttons 22, 24, and 26 that are preferably dedicated toremotely controlling the infusion pump 50, for example, via the RFtransmitter 15 (or RF transceiver 19 (as shown in FIG. 4(b)) or 36 (asshown in FIG. 5)), as will be described below. The buttons 22, 24, and26 may also be used to transmit BG measurements to the infusion pump 50.The buttons 22, 24, and 26 may be labeled ‘S’ for “suspend”, ‘B’ for“bolus”, and ‘ACT’ for “activate”. In alternative embodiments, more orless buttons for operating the meter 10 and/or remotely controlling theinfusion pump 50 may be included on the meter 10, and the buttons may belabeled other than as illustrated in FIG. 1. For example, the BG meter10 may include an additional button for operating a lancing device (notshown) that is incorporated into the meter 10. In further alternativeembodiments, the buttons 22, 24, and 26 may be omitted, and the buttons18 and 20 may be used to remotely control the infusion pump 50. In otheralternative embodiments, the buttons 18 and 20 may be omitted, and thebuttons 22, 24, and 26 may be used to operate the BG meter 10, oralternatively, no buttons may be needed to operate the meter 10. Forexample, the meter 10 may include no buttons or other user interface orinput device, and may be controlled using an external device, such as aremote programmer (not shown), the infusion pump 50, a PDA, or the like.In yet other alternative embodiments, one or more of the buttons 18, 20,22, 24, and 26 may be omitted, and the user may utilize other inputdevices to interface with the BG meter 10, such as selecting a menuitem, utilizing the display 16 as a touch screen, pressingmulti-function keys, or the like.

In addition to transmitting the BG measurement to the infusion pump 50,the BG meter 10 also preferably stores the BG measurement in the memory30 of the BG meter 10 for subsequent analysis and review. A history ofalarms or error messages generated by the BG meter 10, as well as remotecontrol commands sent to and/or information received from the infusionpump 50, may also be stored in the memory 30 of the BG meter 10.Further, the user may periodically cause the BG meter 10 to download thestored data through an interface (such as the RF transmitter 15 (or RFtransceiver 19 (as shown in FIG. 4(b)) or 36 (as shown in FIG. 5)), acable, a communication station, a cradle, or the like), to a computer 34(e.g., desktop or portable computer, such as a laptop or personal dataassistant (PDA)), or alternatively, over the Internet to a remote serverfor storage. The user or a caregiver (e.g., the user's parent, healthcare professional, educator) can evaluate the user's therapy byaccessing the historical BG measurements and insulin deliveryinformation downloaded from the pump 50, as will be described below. Inother embodiments, the BG meter 10 may also obtain information from thecomputer 34 or remote server. It is therefore possible for informationto be shared or transferred in either direction between the BG meter 10and the computer 34 or remote server. In particular embodiments, aconnector 32 may be inserted into the test strip port 11 to provide awired connection to a USB, serial, or the like port of the computer 34,and data may be transferred through the connector 32 between the BGmeter 10 and the computer 34. Alternatively, the computer 34 may be usedin conjunction with a communications device (not shown) that allows theBG meter 10 or other devices, such as insulin pumps, to communicate withthe computer 34. Examples of such communications devices include,without limitation, the ComLink™ available from Medtronic MiniMed, IRcradles, RF devices, or the like that can be used to send and/or receivesignals. For instance, the ComLink™ or other RF device may be connectedto the computer 34 via a wired connection, and the BG meter 10 maytransfer data wirelessly to and from the computer 34 through theComLink™ or other RF device using RF communication. In another instance,the IR cradle may be connected to the computer 34 via a wired orwireless connection, and the BG meter 10 may be placed in the IR cradleand transfer data to and from the computer 34 through the IR cradle.

The transfer of data between the BG meter 10 and the computer 34 orremote server may be transparent and performed without any userinvolvement, so that the user is not aware each time a data transfer isperformed, except for any involvement the user may have had in settingup the transparent data transfer. Information may be transferred at therequest of the user, at predetermined time intervals, or at any otherinterval. For example, the computer 34 may send out a communicationsignal (a ping) and listen for a response from the BG meter 10, whichmay respond to the ping through the interface (such as the RFtransmitter 15 (or RF transceiver 19 (as shown in FIG. 4(b)) or 36 (asshown in FIG. 5)), a cable, a communication station, a cradle, or thelike) to the computer 34. In response to the ping, the BG meter 10 mayeither transmit information to the computer 34 or download informationfrom the computer 34. If the BG meter 10 is within the communicationrange of the computer 34, then the BG meter 10 will be able to downloadinformation from the computer 34 or transmit information to the computer34. The BG meter 10 may also communicate with the computer 34 every timeit is placed in a cradle (not shown) that is connected to the computer34.

In further embodiments, the BG meter may be configured to download data(or transmit data) at a certain scheduled time. For example, the BGmeter may communicate with the computer when the user is expected to bestationary and in a known location, such as when the user is sleeping.In such instance, a bedside monitor may be used to communicate betweenthe BG meter and the computer. The bedside monitor may include a clock,communication capabilities, and a means for passing information to thecomputer. At a predetermined time, the bedside monitor will initiate acommunication protocol attempting to communicate with the BG meter orother devices, such as an infusion pump, a BG sensor, other medicaldevices, and the like. If one or more devices respond to the bedsidemonitor communication, they will send information to the bedsidemonitor. The bedside monitor will pass the information from the one ormore devices to a storage and/or display device such as a computer, apersonal data assistant, or the like. The bedside monitor may also passinformation from the storage and/or display device to another device,such as the infusion pump, BG meter, BG sensor, or other medical device.The bedside monitor may use one or more modes of communication with thestorage and/or display device, such as wired communication, RF, infrared(IR) and the like. The bedside monitor may also be a computer or part ofa computer.

In various embodiments, only the BG meter 10 may be used for downloadinginformation to the computer 34. Thus, the BG meter 10 can communicatewith and receive information for downloading to the computer 10 fromother devices, such as the infusion pump 50 or a BG sensing device (aswill be described below), through the communication system, which mayinclude the RF transmitter 15 or RF transceiver 19 (as shown in FIG.4(b)) or 36 (as shown in FIG. 5)). The BG meter keeps track ofinformation received from the other devices, so each time the BG metercommunicates with the other devices, the BG meter receives only new datafrom the other devices (i.e., data not yet received by the BG meter). Inmore particular embodiments, the BG meter receives new information fromthe other devices when the BG meter sends BG values to the otherdevices. In alternative embodiments, a device other than the BG metermay be used to gather data from the other devices, and to transfer datato the other devices and the computer or other storage device.

In further embodiments, two or more devices may share informationbetween them. For example, a user may use two BG meters—one at home andone at work. If the two or more devices establish contact with eachother, they share information that has been generated since the lasttime they communicated. For example, if the devices are two BG meters,they may send their respective BG measurements to each other so thateach BG meter will have a complete record of BG measurements. In otherembodiments, the two devices are not the same type of device. Forexample, one device may be a BG meter and the other device may be aninsulin pump. The communication between the two or more devices may takeplace upon the user's instruction, whenever either device receives newdata, or at other desired intervals.

Any of the communication described above with respect to the BG meter 10is also possible to create with the insulin pump 50. For example, theinsulin pump may download data to, and/or obtain information from, acomputer or remote server, through an interface or communication system(as will be described below). It is possible for information to beshared or transferred in either direction between the insulin pump 50and a computer or remote server. The transfer of data may betransparent, so that the user is not aware of the transfer while it ishappening. Information may be downloaded at the request of the user, atpredetermined time intervals, or at any other interval. The computer maysend out a communication signal (a ping) and listen for a response fromthe insulin pump, which may respond to the ping through the interface orcommunication system described below. In response to the ping, theinsulin pump may either transmit information to the computer or downloadinformation from the computer. If the insulin pump is within thecommunication range of the computer, then the insulin pump will be ableto download information from the computer or transmit information to thecomputer. The insulin pump may also communicate with the computer everytime it is placed in a cradle that is connected to the computer.Further, the insulin pump and the BG meter may be configured to eachcommunicate with the computer at the same time or in turn.

In further embodiments, the BG meter 10 is in communication with one ormore sensing devices. For example, FIG. 6 shows an embodiment of asensing device 21 that may be in communication with the BG meter 10. Thesensing device 21 is preferably in contact with a bodily fluid (e.g.,blood, interstitial fluid, or the like) of the user through sensor 31,and measures analyte levels of the user. For example, the sensor 31 maybe adapted for insertion in subcutaneous or other tissue of the user,and may measure BG levels of the user. Alternatively, the sensing device21 may measure physiological characteristics other than the user's BGlevels, such as heart rate, respiratory rate, pH, oxygen, ketones,lactose, alcohol levels, and any other desired physiologicalcharacteristics. Sensing device 21 preferably also includes atransmitter 41, which is shown as being capable of wirelesscommunication with the BG meter 10, but may be connected to the BG meter10 through other means, such as a cable. In addition, transmitter 41 maybe located on the same housing as sensor 31 or separated by a cable orother connection. The use of the term “transmitter” is not in any waymeant to be limiting and may refer to any component that may be used totransfer the signal from the sensor to another device. Sensing devicesthat may be used include, but are not limited to, those described inU.S. Pat. No. 6,248,067 issued Jun. 19, 2001; U.S. Pat No. 6,424,847issued Jul. 23, 2002; U.S. Pat No. 6,558,320 issued May 6, 2003; and6,641,533 issued Nov. 4, 2003, and U.S. patent application Ser. No.09/465,715 filed Dec. 17, 1999 and entitled “Telemetered CharacteristicMonitor System and Method of Using the Same”; Ser. No. 10/180,732 filedJun. 26, 2002 and entitled “Communication Station and Software forInterfacing with an Infusion Pump, Analyte Monitor, Analyte Meter, orthe Like”; Ser. No. 10/034,139 filed Dec. 27, 2001 and entitled “SystemFor Monitoring Physiological Characteristics”; Ser. No 10/750,080 filedDec. 31, 2003 and entitled “System For Monitoring PhysiologicalCharacteristics”; Ser. No. 10/429,385 filed May 5, 2003 and entitled“Handheld Personal Data Assistant (PDA) with a Medical Device and Methodof Using the Same”; Ser. No. 10/141,375 filed May 8, 2002 and entitled“Real Time Self-Adjusting Calibration Algorithm for an InterstitialGlucose Concentration”; Ser. No. 10/036,093 filed Dec. 28, 2001 andentitled “Sensing Apparatus and Process”; and Ser. No. 10/750,978 filedDec. 31, 2003 and entitled “Real Time Self-Adjusting CalibrationAlgorithm,” and U.S. patent application Ser. No. 10/860,114 filed Jun.3, 2004 and entitled “System for Monitoring PhysiologicalCharacteristics”, which are herein incorporated by reference. In variousembodiments, the sensing device 21 continuously measures analyte levels,such as BG levels, of the user. Alternatively, the sensing device 21 canmeasure the user's analyte levels intermittently and/or as desired bythe user. For example, the sensing device 21 may measure the user'sanalyte levels approximately every minute, although measurements may betaken at shorter or longer time intervals (e.g., one second, tenseconds, thirty seconds, two minutes, five minutes, or the like). The BGmeter 10 may be adapted to receive sensor values from the sensing device21 continuously, intermittently, or at other desired times.

The BG meter 10 can display sensor values received from the sensingdevice 21, which are related to the user's analyte levels measured bythe sensing device 21. For example, the BG meter 10 displays BG sensorvalues that are refreshed every one, five, ten, fifteen, or twentyminutes, or at other time intervals. Alternatively, the BG meter 10 maydisplay BG sensor values in response to a request from the userutilizing the buttons 18 and 20 of the BG meter 10. The BG meter 10 mayalso provide the user with an alarm visually on the display 16, audiblyvia a speaker, and/or tactilely via a vibration alarm if the sensorvalues are either above or below certain predetermined levels, such asto indicate hypoglycemic or hyperglycemic conditions. The user mayutilize the buttons 18 and 20 on the BG meter 10 to set hypoglycemicand/or hyperglycemic BG levels, or alternatively, these BG levels may bepredefined for the BG meter 10 (e.g., hypoglycemic BG level of 70 mg/dland hyperglycemic BG level of 200 mg/dl). In particular embodiments, theBG meter 10 calibrates the sensor values received from the sensingdevice 21. The calibration can be achieved by any known method, such ascalibration based upon test strip readings taken by the BG meter 10. Forexample, whenever the user tests his BG by using a test strip, the BGmeter 10 can compare this reading to the readings from the sensingdevice 21. If the sensor value is substantially different than the teststrip value, the BG meter 10 will then adjust the sensor value to obtaina calibrated sensor value. Further discussion of methods of calibrationcan be found in U.S. Pat. No. 6,424,847, and U.S. patent applicationSer. No. 09/465,715 filed Dec. 17, 1999 and entitled “TelemeteredCharacteristic Monitor System and Method of Using the Same”; Ser. No.10/141,375, filed May 8, 2002 and entitled “Real Time Self-AdjustingCalibration Algorithm for an Interstitial Glucose Concentration”; andSer. No. 10/750,978 filed Dec. 31, 2003 and entitled “Real TimeSelf-Adjusting Calibration Algorithm,” which are herein incorporated byreference. The BG meter 10 can take into account an estimated period oftime that it takes a user to obtain a test strip blood sample and insertit into the BG meter 10. It is also possible to use other methods tocalibrate the sensor values. For example, each sensor value can becalibrated based upon the history of sensor values. The sensing device21 may include a processor (e.g., microprocessor, application specificintegrated circuit or the like) for calibration of values, control ofthe device, and other processing. The sensing device 21 may furtherinclude a user interface (not shown) for input by the user, which may bewired to the transmitter 41 or may communicate with the transmitter 41through wireless transmission. In further embodiments, the calibrationcan take place at the sensing device 21 instead of or in addition to atthe BG meter 10. In this case, the BG meter 10 transmits a BGmeasurement to the sensing device 21 via a wired or wirelesstransmission, and the BG measurement is used to calibrate the BG sensorvalues measured by the sensing device 21. Alternatively, the BGmeasurement may be manually entered by the user into the sensing device21 utilizing the user interface on the sensing device 21. The BG meter10 then receives the calibrated sensor values from the sensing device21, and may display the calibrated sensor values or other BG valuesrelated to the calibrated sensor values. In further embodiments, thesensing device 21 may include a display (not shown), which may be wiredto the transmitter 41 or may communicate through wireless transmission.The display of the sensing device 21 may also show the raw sensor dataand/or calibrated sensor data. The sensing device 21 may further providethe user with an alarm visually on the display, audibly via a speaker,and/or tactilely via a vibration alarm if the sensor values are eitherabove or below certain predetermined levels, such as to indicatehypoglycemic or hyperglycemic conditions. The user may utilize the userinterface of the sensing device 21 to set hypoglycemic and/orhyperglycemic BG levels, or alternatively, these BG levels may bepredefined for the sensing device 21 (e.g., hypoglycemic BG level of 70mg/dl and hyperglycemic BG level of 200 mg/dl). Additionally, if the BGmeter 10 is used in connection with an infusion pump, the sensor datamay be transmitted from the BG meter 10 and/or the sensing device 21 tothe infusion pump.

In the embodiment illustrated in FIGS. 1 and 2, the electronic computingdevice is an insulin delivery device, preferably an external insulininfusion pump 50. The infusion pump 50 regulates the flow of fluid fromthe infusion pump 50, through a flexible tube 54, and into an infusionset 56 or the like that is adhered to the individual. Infusion sets 56that may be used as a delivery device are described in, but not limitedto, U.S. Pat. Nos. 4,723,947; 4,755,173; 5,176,662; 5,584,813; and6,056,718, which are herein incorporated by reference. The infusion pump50 may be of the type described in U.S. Pat. Nos. 4,562,751; 4,685,903;5,080,653; 5,097,122; 5,505,709; and 6,248,093; and disclosed in U.S.patent application Ser. No. 09/334,858 filed Jun. 17, 1999 and entitled“Infusion Pump With Remote Programming and Carbohydrate CalculatorCapabilities,” which are herein incorporated by reference. Such infusionpumps 50 may be adapted to be carried by the user, for example, in thehand, on the body, in a clothing pocket, attached to clothing (e.g.,using a clip, strap, adhesive, or fastener), and the like.Alternatively, other infusion pumps 50 may be used for delivery of fluidthrough an infusion set 56 into an individual's body. In furtheralternative embodiments, devices other than infusion pumps 50 may beused for delivery of fluid into an individual's body, such as animplantable insulin infusion pump or system that uses a combination ofimplantable and external components, an injection pen, an IV meter, andthe like. In other alternative embodiments, the electronic computingdevice may be a computer, the Internet, a personal digital assistant(PDA), a portable telephone, a custom computing device, and the like.

As illustrated in FIGS. 1 and 2, preferred embodiments of the infusionpump 50 include an RF communication system 60 and a bolus estimator 62.In particular embodiments, the RF communication system 60 includes an RFreceiver 80, as shown in FIG. 3(a), which allows one-way communicationfrom the BG meter 10 (or other external devices such as a remoteprogrammer for the infusion pump 50) to the infusion pump 50. In otherparticular embodiments, the RF communication system 60′ may include anRF transceiver 81, as shown in FIG. 3(b), which allows two-waycommunication between the BG meter 10 (or other external devices such asa remote programmer for the infusion pump 50) and the infusion pump 50.

The RF communication system 60 and bolus estimator 62 communicate with aprocessor 64 contained in a housing 52 of the infusion pump 50. Theprocessor 64 is used to run programs and control the infusion pump 50,and is connected to an internal memory device 66 that stores programs,history data, user defined information and parameters. In preferredembodiments, the memory device 66 is a ROM and DRAM; however, inalternative embodiments, the memory device 66 may include other memorystorage devices, such as RAM, EPROM, non-volatile memory, dynamic orsemi-dynamic storage such as flash memory, energy efficient hard-drive,or the like. In the illustrated embodiment, the processor 64 is alsocoupled to a drive mechanism 72 that is connected to a fluid reservoir74 containing fluid, which is delivered through an outlet 76 in thereservoir 74 and housing 52, and then into the user's body through thetubing 54 and the infusion set 56.

The infusion pump 50 is preferably programmed through a user inputdevice such as a keypad 58 on the housing 52, or alternatively, bycommands received from an RF programmer (not shown) through the RFcommunication system 60. The infusion pump 50 may also be programmedthrough the keypad 28 on the BG meter 10, for example, through the RFcommunication system 60, as will be described below. Feedback to theinfusion pump 50 on status or programming changes are shown on a display68, audibly through a speaker 70, and/or tactilely through a vibrationalarm 78. The infusion pump 50 may also provide the user with an alarmeither audibly via the speaker 70 and/or tactilely via the vibrationalarm 78, such as a warning that is indicative of a low reservoirsituation or low battery. Alarms may start out at a low level andescalate until acknowledged by the user. In alternative embodiments, thekeypad 58 may include more or less keys or different key arrangementsthan those illustrated in FIG. 1. In further alternative embodiments,the keypad 58 may be omitted, and the display 68 may be used as a touchscreen input device. In other alternative embodiments, the keypad 58,display 68, speaker 70, and/or vibration alarm 78 may be omitted, andall programming and data transfer may be handled through the RFcommunication system 60.

In particular embodiments, one-way communication is provided from the BGmeter 10 to the infusion pump 50. The BG meter 10 includes the RFtransmitter 15 (shown in FIG. 4(a)), and the infusion pump 50 includesan RF receiver 80 (shown in FIG. 3(a)). In other particular embodiments,two-way communication is provided between the BG meter 10 and theinfusion pump 50. The RF transmitter 15 in the BG meter 10 is replacedwith an RF transceiver 19 (shown in FIG. 4(b)) or 36 (shown in FIG. 5),and the RF receiver 80 in the infusion pump 50 is replaced with an RFtransceiver 81 (shown in FIG. 3(b)).

The infusion pump 50 may provide several programming options, includingthe bolus estimator 62, as well as remote and on-device programming. Theinfusion pump 50 may also be configured through an interface, such as acable or communication station, using a computer or the like.Additionally, the infusion pump 50 may allow the user to downloadinformation in the memory 66 through the interface to a computer or thelike, or alternatively, over the Internet to a remote server, forstorage. Further description of a communication station of this generaltype may be found in U.S. Pat. No. 5,376,070, which is hereinincorporated by reference. The user or a caregiver (e.g., the user'sparent, health care professional, educator) can evaluate the user'stherapy by accessing the historical BG measurements downloaded from theBG meter 10 and insulin delivery information downloaded from the pump50. In other embodiments, the infusion pump 50 may also obtaininformation from the computer or remote server. It is thus possible totransfer information in either direction between the infusion pump 50and the computer or remote server.

Information may also be downloaded from, or received by, the infusionpump 50 through the RF communication system 60. Referring to FIG. 3(b),the RF communication system 60′ may include the RF transceiver 81 fortransmitting information to and receiving information from externaldevices. In particular embodiments, an external communication link (notshown) may be connected to a serial, USB, or the like port of acomputer. Information may be transmitted from the RF transceiver 81 inthe infusion pump 50 to an RF transceiver in the external communicationlink (not shown), which then downloads the information through a wiredconnection to the computer or the like. During the download process, thecommunication link may draw power from the computer through the serial,USB, or the like port. In other particular embodiments, the connector 32may be inserted into the test strip port of the BG meter 10′ to providea wired connection to a USB, serial, or the like port of the computer34, as shown in FIG. 4(b). Information may be transmitted from the RFtransceiver 81 in the infusion pump 50 to the RF transceiver 19 in theBG meter 10′, and may then be downloaded through the connector 32 to thecomputer 34. The BG meter 10′ merely functions as a “pass through”connection between the infusion pump 50 and the computer 34. During thedownload process, power may be drawn from the power supply (not shown)for the BG meter 10′ (e.g., battery or the like), or alternatively, fromthe USB, serial, or the like port of the computer 34. In still otherparticular embodiments, information may be transmitted from the RFtransceiver 81 in the infusion pump 50 to the RF transceiver 36 in theBG meter 10″, as shown in FIG. 5. The information may be transmittedfrom the infusion pump 50 to the BG meter 10″ at a rate higher than canbe handled by the meter processor 17″. Accordingly, the BG meter 10″ mayinclude a communications microcontroller or processor 38 with a higherprocessing speed (e.g., 10 MHz) than the meter processor 17″ with alower processing speed (e.g., 1-4 MHz). The transmitted information isfirst processed by the communications processor 38, then processed bythe meter processor 17″, and finally downloaded through the connector 32to the computer 34. Again, the BG meter 10′ merely functions as a “passthrough” connection between the infusion pump 50 and the computer 34. Inalternative embodiments, information may be transmitted from theinfusion pump 50 and stored in the memory 30′ or 30″ of the BG meter 10′or 10″ for subsequent downloading from the BG meter 10′ or 10″ to thecomputer 34. In further alternative embodiments, information may betransmitted from the infusion pump 50 through the BG meter to thecomputer 34 using other modes of communication, such as infrared,optical, or the like. In other embodiments, information may be receivedby the infusion pump 50 from the computer.

Devices such as the infusion pump 50, BG meter 10, and sensing device 21may learn each other's serial number and agree to listen to each other.Devices may also learn other identifying numbers or other characters orindicia, which may be unique, of each other (e.g., identificationnumber, password, or the like). Communications among devices may includethe unique identifying numbers or other identification information forone or more of the devices, and the devices utilize these uniqueidentifying numbers or other identification information to discernbetween communications that are intended for the particular device andthose that are not. The identifying numbers or other identificationinformation may be chosen by a user or may be provided for the user (forexample, a serial number could be added by the manufacturer orsupplier). As an example, a user may place a pump into a mode so that itis ready to receive a signal from a meter containing the meter's serialnumber. When the signal is received, the user may tell the pump toaccept and store the identifying number from the meter so that the pumpcan hear and accept other information from the meter in the futurewithout requiring the user's approval, or the user can tell the pump toreject and not store the identifying number from the meter. If the pumpstores the meter's identifying number, then future communicationscontaining that identifying number will be accepted by the pump. Theuser may alternatively key in the identifying number through a userinterface. Other devices may accept identifying numbers from still otherdevices. For example, in addition to the identifying number from themeter, the pump may also accept an identifying number from the sensingdevice. In alternative embodiments, a meter can send a signal to a pumpwithout requiring that the user place the pump into a mode to receive asignal from the meter. When the pump detects the signal, the user cantell the pump to accept or reject the signal. The user can set the pumpinto a mode to not listen to unsolicited information (for example,signals from devices whose identifying numbers are not already in thepump). Additionally, in particular embodiments, devices will offer theiridentifying numbers to other devices without any interaction by theuser.

Communication by devices between each other and with computer and otherstorage devices can be achieved through the use of any availablecommunication architecture. Some examples of communication architectureinclude, without limitation, radio frequency based communication, suchas high frequency radio wave communication like Bluetooth and such aswide bandwidth radio communication like spread spectrum, ultrasoniccommunication, and infrared communication.

In further embodiments, as shown in FIG. 7, the infusion pump 50 maycommunicate with sensing device 21 instead of, or in addition to, the BGmeter. The sensing device 21 may be connected to the infusion pump 50 bya wire, or communication between the infusion pump 50 and the sensingdevice 21 may be wireless. The infusion pump 50 may be adapted toreceive sensor values including the user's measured analyte levels fromthe sensing device 21 continuously, intermittently, or at other desiredtimes. The infusion pump 50 can then be used in conjunction with the BGmeter 10, which transmits BG measurements to the infusion pump 50. TheseBG measurements may be used to calibrate the sensor values received fromthe sensing device 21. The raw or calibrated sensor values, as well asthe BG measurements transmitted by the BG meter 10, can be displayed onthe infusion pump display 68. For example, the infusion pump 50 maydisplay BG sensor values that are refreshed every one, five, ten,fifteen, or twenty minutes, or at other time intervals. Alternatively,the infusion pump 50 may display BG sensor values in response to arequest from the user utilizing the keypad 58 of the infusion pump 50.The infusion pump 50 may also provide the user with an alarm visually onthe display 68, audibly via the speaker 70, and/or tactilely via thevibration alarm 78 if the sensor values are either above or belowcertain predetermined levels, such as to indicate hypoglycemic orhyperglycemic conditions. The user may utilize the keypad 58 of theinfusion pump 50 to set hypoglycemic and/or hyperglycemic BG levels, oralternatively, these BG levels may be predefined for the infusion pump50 (e.g., hypoglycemic BG level of 70 mg/dl and hyperglycemic BG levelof 200 mg/dl). The infusion pump 50 may further display BG trends orgraphs, provide the user with additional information, and/or includeother features as described and disclosed in U.S. patent applicationSer. No. 10/860,114 filed Jun. 3, 2004 and entitled “System forMonitoring Physiological Characteristics”, which is herein incorporatedby reference. By enabling communication between the sensing device 21and the infusion pump 50 in this way, the user is required to wear feweror less bulky devices. For example, the sensing device 21 does notrequire a display because the sensor values can be transmitted to andshown on the infusion pump 50. Also, the sensing device 21 does not needto calibrate the sensor values prior to transmitting them to theinfusion pump 50 because the sensor values can be calibrated by theinfusion pump 50 utilizing BG measurements received from the BG meter10.

In further embodiments, when a BG value is above or below certainpredetermined levels, such as when the user is experiencing hypoglycemiaor hyperglycemia, the system will automatically call a service forassistance, for example, the system may dial a 911 operator. Dependingon which device communicates with the sensing device 21, it is possiblethat either the BG meter 10 or the infusion pump 50 (or the sensingdevice 21 itself) may call the service for assistance. Additionally, thecall for assistance may include a global positioning service (GPS)location, when the device establishing the call includes a GPS locator.The sensing device 21 may also measure and display physiologicalcharacteristics in addition to the user's BG levels, such as heart rate,respiratory rate, pH, oxygen, ketones, lactose, alcohol levels, and anyother desired physiological characteristics. These characteristics maybe displayed on the device and also may be sent to the assistanceservice if they reach certain emergency levels.

In preferred embodiments, the infusion pump 50 communicates with variousexternal devices, such as the BG meter 10, a remote programmer, and acommunication station, using the RF communication system 60, which willbe described below. The infusion pump 50 also provides a confirmation tothe user upon receipt of a communication from another device (e.g., theBG meter 10). In particular embodiments, the infusion pump 50 providesone or more audible signals when it has received a communication. Morethan one audible signal may be used, and each audible signal indicatesthe type of communication that was received. For example, the infusionpump 50 may beep 4 times when it has received a communication to deliver0.4 units of insulin in a bolus, provide a long low tone when it hasreceived a communication to suspend insulin delivery, and/or sound offwith a two-tone “door bell” sound when a new BG measurement has beencommunicated. In alternative embodiments, the infusion pump 50 mayprovide other forms of confirmation when a communication has beenreceived, such as one or more vibrations via the vibration alarm 78,messages on the display 68, lights or flashing lights, or the like.

In preferred embodiments, once the BG meter 10 obtains a BG measurement,the BG meter 10 automatically transmits the BG measurement to theinfusion pump 50. In particular embodiments, the BG meter 10 analyzesthe blood sample 14 on the test strip 12 to calculate a BG measurementand then transmits the BG measurement to the infusion pump 50 withoutadditional effort by the user. In alternative embodiments, the BGmeasurement is transmitted when the test strip 12 is removed from the BGmeter 10. In other alternative embodiments, the BG meter 10 transmitsthe BG measurement in response to an action by the user. The BG meter 10may also retransmit the BG measurement to the infusion pump 50 inresponse to a user action, such as pressing a button, selecting a menuitem, or holding down a button on the BG meter 10, aligning the BG meter10 and the infusion pump 50, or the like. In alternative embodiments,the BG meter 10 is notified by the infusion pump 50 to transmit orretransmit the BG measurement.

Once the infusion pump 50 receives the BG measurement, the infusion pump50 may provide an alarm or warning to the user if the received BGmeasurement is above or below glycemic limits. The glycemic limits arepreferably programmable, such as 120 mg/dl for hyperglycemia and 60mg/dl for hypoglycemia. The user, a caregiver, a physician, a parent, aguardian, a child, or the like may program other limits into theinfusion pump 50. In alternative embodiments, the glycemic limits arenot programmable. In preferred embodiments, the infusion pump 50 willsuspend insulin delivery if the received BG measurement is below thehypoglycemic limit. The infusion pump 50 may also notify the user toactivate a bolus delivery if the received BG measurement is above thehyperglycemic limit. In alternative embodiments, the infusion pump 50does not compare the received BG measurement to glycemic limits, anddoes not suspend insulin delivery in the event of hypoglycemia or notifythe user to activate bolus delivery in the event of hyperglycemia.

In preferred embodiments, the infusion pump 50 also stores the receivedBG measurement in its memory 66. Further, the bolus estimator 62 in theinfusion pump 50 may utilize the received BG measurement to calculate abolus estimate, either automatically or in response to user input, suchas through the keypad 58, a remote programmer, or the like. Once thebolus estimate is calculated and provided to the user, for example, onthe display 68, the user may then approve the recommended estimate fordelivery into the body, modify the recommended estimate for deliveryinto the body, or reject the recommended estimate. The bolus estimator62 may generally be of the type and/or include features disclosed inU.S. patent application Ser. No. 09/334,858 filed Jun. 16, 1999, nowissued U.S. Pat. No. 6,554,798 issued Apr. 29, 2003.

The BG meter 10 preferably informs the user of the status of the BGmeasurement calculation and/or transmission. If the infusion pump 50 iscapable of only one-way communication, such notification is preferablebecause no confirmation is received from the infusion pump 50 indicatingthat the transmitted data has been received by the pump 50. The BG meter10 may notify the user when a blood sample is being analyzed to obtain aBG measurement. The BG meter 10 may also notify the user when the BGmeasurement is being transmitted to the infusion pump 50. The BG meter10 may further notify the user when the transmission of the BGmeasurement is complete. Once notified that the transmission of the BGmeasurement is complete, the user may access the bolus estimator 62 inthe infusion pump 50 to view the BG measurement and calculate a bolus.In preferred embodiments, the BG meter 10 displays the status on thedisplay 16, for example, as an alphanumeric message, a graphical icon,or the like. In alternative embodiments, the status is communicated tothe user in other ways, such as using one or more light emitting diodes,one or more audible tones, a speaker, a piezo electric device, avibrator or other tactile device, or the like. In further alternativeembodiments, the BG meter 10 may not provide the status to the user. Forexample, if the BG measurement device provides continuous or automaticintermittent BG measurements, the user is not perpetually notifiedregarding the status of the calculations and/or transmissions.

In preferred embodiments, the BG meter 10 keeps track of the elapsedtime between when a BG measurement is collected and when it iscommunicated to the infusion pump 50 for calculating a bolus estimate. ABG measurement is preferably used to calculate a bolus estimate only ifthe BG measurement is recent enough. The bolus estimation is at leastpartially dependent on the difference between the user's present BGlevel and a desired target BG level. Since a user's BG level varies overtime, using an old BG measurement to calculate a bolus estimation mightresult in a bolus estimation that is inappropriate for the user. A BGmeasurement is expired (and is not used for bolus estimation) when it istoo old to be considered representative of the user's present BG level.The BG meter 10 does not transmit a BG measurement to the infusion pump50 for use in a bolus estimation calculation if the BG measurement isexpired. The BG meter 10 may also indicate to the user that a new BGmeasurement is required because the BG measurement is expired orunavailable. In preferred embodiments, the BG measurement expires at 10minutes. In alternative embodiments, the BG measurement may expire in anamount of time greater or less than 10 minutes, such as 5 or 7 minutes,15 or 30 minutes, 1 hour, or the like. In further alternativeembodiments, the time required for a BG measurement to expire may be setby the user, a caregiver, a physician, a parent, a guardian, a child,and the like. For example, a child's BG level may change more quicklythan that of a heavy adult, so the BG meter 10 may be set so that BGmeasurements older than 5 minutes cannot be communicated to the infusionpump 50 for use in a bolus estimation. To continue the example, an adultmight program the BG meter 10 so that BG measurements expire after 12minutes. Furthermore, the time required for a BG measurement to expiremay be set depending on the time of the user's most recent bolus dose ofmedication. A first period may be set if the user has taken a boluswithin a specified duration of time, and a second period may be set ifthe user has not taken a bolus within the specified duration of time.For example, the time required for a BG measurement to expire may be setto 5 minutes if the user has taken a bolus within the past 2 hours, andto 15 minutes if the user has not taken a bolus within the past 2 hours.

In preferred embodiments, the infusion pump 50 does not use an expiredBG measurement in a bolus estimation calculation. The infusion pump 50preferably keeps track of the time between when a new BG measurement isreceived from the BG meter 10 and when the new BG measurement is used ina bolus estimation calculation. In particular embodiments, once the BGmeter 10 obtains a BG measurement, the BG measurement is immediatelytransmitted to the infusion pump 50, either automatically or in responseto a user action. Thus, when the infusion pump 50 receives a BGmeasurement, the pump 50 knows that the BG measurement was recent, andcan calculate the approximate age of the BG measurement simply bydetermining the amount of time that has elapsed between when the BGmeasurement was received from the BG meter 10 and when the BGmeasurement is used in a bolus estimation calculation. In otherparticular embodiments, the infusion pump 50 is told the age of the BGmeasurements it receives. In other words, the elapsed time between whena BG measurement is collected and when it is communicated to theinfusion pump 50 is transmitted along with each BG measurement. Then,the infusion pump 50 can calculate the age of the BG measurement byadding the age of BG measurement at the time it was transmitted to thetime that has passed since the BG measurement was received. Since theinfusion pump 50 knows the age of the BG measurement, the infusion pump50 can eliminate BG measurements that are expired and/or prevent expiredBG measurements from being used in a bolus estimation calculation. Inparticular embodiments, the infusion pump 50 will request a new BGmeasurement from the user when the user attempts to use a bolusestimator and the BG measurement is expired or unavailable.

In alternative embodiments, an estimate of the user's BG level is usedfor bolus estimation. In particular alternative embodiments, the user'sBG level is estimated using the last BG measurement, the age of the BGmeasurement, the amount of insulin that has been delivered, the insulinaction time, the number of carbohydrates consumed, thecarbohydrate/insulin ratio, and the like. In further alternativeembodiments, the estimate of the user's BG level will expire if not usedsoon enough. In still further alternative embodiments, the estimate ofthe user's BG level may only be calculated for a certain period after aBG measurement is collected. In other alternative embodiments, thelength of time that a BG estimate may be calculated since a BGmeasurement was collected is determined by the amount of insulin thathas been delivered, the amount of carbohydrates the user has ingested,the user's insulin sensitivity, and/or by the user's insulin actiontime. For example, estimates of BG levels may be calculated for a longerperiod if the user has not eaten lately and is using only basal insulin.If the user has eaten or taken a bolus of insulin, then the period oftime that an estimate of the user's BG level might be calculated isshorter.

In preferred embodiments, the BG meter 10 communicates with the infusionpump 50 using RF communication. In alternative embodiments, other modesof communication may be used, such as infrared (IR), wired, ultrasonic,sonic, optical, and the like. The BG meter 10 transmits one or more BGmeasurements to the infusion pump 50. The BG meter 10 may alsocommunicate one or more remote control commands to the infusion pump 50.The available commands preferably include a bolus amount of insulin, acommand to begin insulin delivery, and a command to suspend insulindelivery. In alternative embodiments, more or less remote controlcommands may be provided between the BG meter 10 and the infusion pump50. The RF transmitter 15 (or RF transceiver 19 (as shown in FIG. 4(b))or 36 (as shown in FIG. 5)) in the BG meter 10 transmits the data (e.g.,BG measurements or remote control commands) to the RF communicationsystem 60 in the infusion pump 50. Additionally, the infusion pump 50may communicate one or more user-defined parameters to the BG meter 10(e.g., the time required for a BG measurement to expire). The RFtransceiver 81 in the infusion pump 50 (shown in FIG. 3(b)) transmitssuch parameters to the RF transceiver 19 (as shown in FIG. 4(b)) or 36(as shown in FIG. 5) in the BG meter 10′ or 10″.

In preferred embodiments, communication between the BG meter 10 and theinfusion pump 50 contains unique identifying information about the BGmeter 10 and/or infusion pump 50, such as the BG meter's 10 and/orinfusion pump's 50 serial number, identification number, a password, acode, or the like. In particular embodiments, the unique identifyinginformation about the BG meter 10 and/or infusion pump 50 included inthe communication between the BG meter 10 and the infusion pump 50 isused by the respective devices (i.e., BG meter 10 and/or infusion pump50) to discern between communications that are intended for the deviceand those that are not. In alternative embodiments, other codes may beincluded in communications between the BG meter 10 and the infusion pump50 that are used by the respective devices to recognize whichcommunications are intended for the device, such as an identificationcode for the device, a password, a bit sequence, a special frequency,timing between communications, or the like.

In preferred embodiments, the communication system in the BG meter 10may be deactivated, preferably by the user. When the communicationsystem is deactivated, the BG meter 10 will not attempt to communicatewith other devices, including the infusion pump 50. For example, when anew BG measurement is available, the BG meter 10 will not communicatethe BG measurement to another device, such as the infusion pump 50. Inparticular embodiments, the BG meter 10 includes an RF transmitter 15(shown in FIG. 4(a)) (or RF transceiver 19 (shown in FIG. 4(b)) or 36(shown in FIG. 5)) that can be deactivated and reactivated by the user.This is especially useful if the BG meter 10 transmits at frequenciesthat might disrupt an airplane during take-off. In alternativeembodiments, other devices may be used to deactivate and reactivate thecommunication system in the BG meter 10, such as the infusion pump 50,other insulin delivery device, a computer, PDA, portable telephone, orthe like. In preferred embodiments, the BG meter 10 may be programmed toreactivate its communication system after a certain duration. Inparticular embodiments, when the user deactivates the BG meter'scommunication system, the user is prompted to enter a duration for howlong communication system is to be deactivated, and the communicationsystem will automatically become active at the end of the duration. Inalternative embodiments, the user may specify a time of day for thecommunication system to become active. In particular embodiments, all ofthe BG measurements that have been generated while the communicationsystem was deactivated are transmitted to the infusion pump 50 when thecommunication system is reactivated. Other data may also be transmittedto the infusion pump 50, such as the BG meter's clock time when the BGmeasurement was generated (i.e., the timestamp for the BG measurement),the age of the BG measurement, and the like.

One-way communication is preferably used between the BG meter 10 and theinfusion pump 50. The BG meter 10 includes a transmitter 15, and theinfusion pump 50 includes a receiver 80. For example, the BG meter 10transmits data (e.g., BG measurements or remote control commands), andthe infusion pump 50 receives this data. The benefits of one-waycommunication (compared to two-way) include cheaper unit costs, lessdevelopment time, and decreased battery power requirements. However, thedrawback of one-way communication is that there is no confirmation thatthe BG meter 10 has transmitted the data to the infusion pump 50.Accordingly, in alternative embodiments, two-way communication may beused, and the BG meter 10 may include a transceiver 19 (as shown in FIG.4(b)) or 36 (as shown in FIG. 5), and the infusion pump 50 may include atransceiver 81 (as shown in FIG. 3(b)).

In preferred embodiments, the infusion pump 50 uses power cycling toperiodically supply power to its communication system. In alternativeembodiments, the infusion pump 50 may not use power cycling, andinstead, may continuously supply power to its communication system. Thepower cycle, which is one period that the communication system is offplus one period that the communication system is on, is preferably 8seconds. In alternative embodiments, the power cycle may be shorter orlonger than 8 seconds, such as 2 or 4 seconds, 12 or 15 seconds, or thelike. Further, the period that the communication system is on duringeach power cycle is preferably 48 milliseconds (ms). In alternativeembodiments, the period that the communication system is on during eachpower cycle may be greater or less than 48 ms, depending on the lengthof the message to be received, the communication frequency, the speed ofthe communication system electronics, and the like. In preferredembodiments, the BG meter 10 sends repeated signals to the infusion pump50 for a period longer than the power cycle. The signal sent from the BGmeter 10 to the infusion pump 50 preferably includes a command that isshort enough to be captured during the on-time of the infusion pump'scommunication system. In particular embodiments, the command is shortenough to be captured multiple times (i.e., two, three, or more times)during the on-time of the infusion pump's communication system.

In preferred embodiments, the time that the infusion pump'scommunication system must be on to capture the command from the BG meter10 is short compared to the power cycle. In further embodiments, thecommand is short compared to a string of information. When the infusionpump 50 receives a command, the infusion pump 50 stops power cycling thecommunication system and turns the communication system on continuously.Alternatively, when the infusion pump 50 receives a command, theinfusion pump 50 may continue to use power cycling unless the commandindicates that the pump 50 should prepare to receive a string ofinformation. Thus, short commands may be used to activate the infusionpump's communication system so that one or more longer strings ofinformation may be received by the infusion pump 50.

In particular embodiments, the infusion pump 50 prepares to receive astring of information longer than a command. The string of informationpreferably includes a BG measurement. The string of information mayfurther include an elapsed time since the BG measurement was taken. Inalternative embodiments, the string of information may include a clocktime. In further alternative embodiments, the BG meter 10 may transmit aclock time to the infusion pump 50 so that the infusion pump 50 candetermine the difference between the BG meter's clock and the infusionpump's clock. In other alternative embodiments, the infusion pump 50 mayuse the BO meter's clock time to reset the infusion pump's clock time.

In preferred embodiments, the infusion pump 50 returns to power cyclingthe communication system after information has been received from the BGmeter 10. In particular embodiments, the infusion pump 50 returns topower cycling after it receives a complete signal containing a BGmeasurement from the BG meter 10. In alternative embodiments, theinfusion pump 50 returns to power cycling at a predetermined periodafter a signal from the BG meter 10 has stopped. In other alternativeembodiments, the infusion pump 50 returns to power cycling at apredetermined period after receiving a signal from the BG meter 10.

As described above, the infusion pump 50 preferably communicates withvarious external devices, such as the BG meter 10, using the RFcommunication system 60. In particular embodiments, the RF communicationsystem 60 includes an RF receiver 80, an RF microcontroller 82 (RF PIC),and an application specific integrated circuit 84 (ASIC), as shown inFIG. 3(a). In other particular embodiments, the RF receiver 80 may bereplaced with an RF transceiver 81, as shown in FIG. 3(b). The RF PIC 82may hold a 7-byte word, although in alternative embodiments, the RF PIC82 may hold other lengths of data. The processor 64 communicates withthe RF PIC 82 and the ASIC 84 using synchronous peripheral interfaces(SPI interfaces).

The RF receiver 80 receives and demodulates RF signals, extracts a datapacket from the RF signal, and passes the data packet to the RF PIC 82.The RF PIC 82 accepts and decodes the data packet and checks for format.If the format of the data packet is valid, the RF PIC 82 sends aninterrupt signal to the ASIC 84. When the ASIC 84 receives an interruptsignal from the RF PIC 82, the ASIC 84 sends an interrupt to theprocessor 64, triggering the processor 64 to notify the RF PIC 82 topass the contents of its buffer to the processor 64. The processor 64acquires the decoded data packet from the RF PIC 82 and evaluates thecontent, which may include a command or information to be stored. Inresponse to some data packets, the processor 64 will send a command tothe ASIC 84 to change the power conditions on the RF receiver 80. Theprocessor 64 also processes the commands and information received fromthe BG meter 10, which may result in changing the bolus delivery on theinfusion pump 50 or entering a BG measurement into the bolus estimator62. One of the main tasks for the ASIC 84 is to enable and disable poweron the RF receiver 80. Generally, the ASIC 84 cycles the power on the RFreceiver 80 to save energy. If commanded by the processor 64, however,the ASIC 84 will enable the RF receiver 80 to be powered continuously.

Each RF transmission sent to the pump preferably includes an RF signalheader followed by a command packet or an information packet. Since thepump's RF receiver 80 is likely to wake up in the middle of a commandpacket, the RF signal header at the start of each transmission helps thepump 50 to synchronize its data sampling and identify the first byte ofa new command packet or information packet. The RF signal header ispreferably the same for each transmission, and is transmitted at thestart of each RF transmission. The RF signal header may include twoparts: a preamble and a start signature. The preamble is a series ofpulses used to train the pump's digital signal sampling, and allows thepump 50 to synchronize its pulse sampling with the pulse bits in the newtransmission. The start signature notifies the pump RF PIC 82 when thefirst byte of a new packet is starting. In alternative embodiments, theRF signal header may include other data. In further alternativeembodiments, the RF signal header may be omitted.

In particular embodiments, command packets are 7 bytes in length, andinformation packets are 71 bytes in length. In alternative embodiments,the command packets and/or information packets may be of differentlengths. The last byte of every command or information packet is an8-bit cyclic redundancy check (CRC) calculated on all the precedingbytes in the packet. Before a command or information packet is sent bythe BG meter 10 to the infusion pump 50, it is encoded using a DCbalanced encoding scheme, which translates 4 bits of data into 6 fortransmission as follows:

HEX DC 0 010101 1 110001 2 110010 3 100011 4 110100 5 100101 6 100110 7010110 8 011010 9 011001 A 101010 B 001011 C 101100 D 001101 E 001110 F011100

The result of the encoding is that the 7-byte command packets requiretransmission of 11 bytes and the 71-byte data packets requiretransmission of 107 bytes. Upon receipt of the 11-byte or 107-bytepackets from the BG meter 10, the pump RF PIC 82 in the infusion pump 50decodes the packet into the 7-byte command packet or the 71-byteinformation packet. The processor 64 then checks all packets for valididentification of the infusion pump 50 (e.g., identification or serialnumber) and CRC. If the identification of the infusion pump 50 is notvalid, the packet is ignored. If the CRC of the first command packet isnot valid, the command is ignored. Otherwise, the processor 64 sends anegative acknowledge (NAK) response to any packet with an invalid CRC.

Information packets (71 bytes) are much larger than command packets (7bytes), and cannot be stored in the pump RF PIC 82, and thus, cannot beused to “wake up” the pump 50. Instead, a command packet must be sent tothe pump 50 to turn on the pump's RF receiver 80 and prepare the pump 50to receive an information packet. While power to the infusion pump'scommunication system (i.e. RF receiver 80) is being cycled, a commandpacket is repeatedly transmitted from the BG meter 10 to the infusionpump 50. If an RF signal (i.e. including the first command packet) ispresent when the pump's RF receiver 80 comes on, the pump 50 willattempt to store the contents of the signal in the pump RF PIC 82. Theprocessor 64 will verify whether the content of the signal is a validcommand packet. If the command packet is valid, then the pump 50 willstop power cycling and power the RF receiver 80 continuously. Only thefirst command packet must be transmitted repeatedly. After the RFreceiver 80 is on full-time, other command packets can be sent to thepump 50 in quick succession (for example, as quickly as the user canpress buttons on the BG meter 10 or other external device to send thenew command packets). Additional command packets or an informationpacket may also be transmitted to the pump 50.

The pump 50 preferably recognizes two categories of command packets:remote control or bolus commands and BG measurement commands. Remotecontrol or bolus commands directly control the pump's insulin bolusdelivery. BG measurement commands may transmit a new BG measurement(s)from the BG meter 10 to the pump 50, or alternatively, prepare the pump50 to receive an information packet containing a new BG measurementvalue as well as other related data (e.g., a clock time or timestamp ofthe BG measurement, the age of the BG measurement, or the like) from theBG meter 10.

The pump 50 may receive a bolus command from the BG meter 10 or a remoteprogrammer associated with the pump 50. The bolus command preferablyincludes a type code indicating the type of device transmitting themessage (e.g., the BG meter 10 or the remote programmer), uniqueidentifying information about the pump 50 (e.g., serial number,identification number, password, or the like), a key code indicatingwhich bolus command button has been pressed (e.g., button “S” 22, button“B” 24, or button “ACT” 26 on the BG meter 10), and a counter indicatingthe number of times that the button has been pressed. In alternativeembodiments, the bolus command may include other information and/or omitsome of this data. When the pump 50 receives the bolus command, theprocessor 64 filters the command to discern the counter value so thatthe pump 50 can respond to the number of times the user has pressed thebutton to adjust a bolus.

The pump 50 may also receive a BG measurement command from the BG meter10. The BG measurement command is transmitted to the pump 50 to send anew BG measurement(s) from the BG meter 10 to the pump 50, oralternatively, to prepare the pump 50 to receive an information packetcontaining a new BG measurement as well as other related data (e.g., aclock time or timestamp of the BG measurement, the age of the BGmeasurement, or the like) from the BG meter 10. If the BG measurementcommand transmits a new BG measurement(s) from the BG meter 10 to theinfusion pump 50, the command preferably includes a type code indicatingthe type of device transmitting the message (e.g., the BG meter 10), theBG measurement value(s), and unique identifying information about themeter 10 and/or pump 50 (e.g., serial number, identification number,password, or the like). If the BG measurement command is transmitted toprepare the pump 50 to receive an information packet containing a BGmeasurement and other related data from the BG meter 10, the commandpreferably includes a type code indicating the type of devicetransmitting the message (e.g., the BG meter 10), unique identifyinginformation about the meter 10 and/or pump 50 (e.g., serial number,identification number, password, or the like), and a key code indicatingthat a new BG measurement is about to be transmitted. In alternativeembodiments, the BG measurement command may include other informationand/or omit some of this data.

In response to communications from the BG meter 10, the pump 50typically sends an acknowledge (ACK) response. However, in particularembodiments, the BG meter 10 does not include an RF receiver, and thepump 50 does not include an RF transmitter, and thus, the pump 50 doesnot send an ACK response if the type code in the command (e.g., bolus orBG measurement command) indicates that the device transmitting themessage is the BG meter 10. In alternative embodiments, both the BGmeter 10 and the pump 50 may include an RF transmitter and receiver(i.e. transceiver 19 (shown in FIG. 4(b)) or 36 (shown in FIG. 5) in theBG meter 10′ or 10″, and transceiver 81 (shown in FIG. 3(b)) in theinfusion pump 50), and thus, the pump 50 may send an ACK response to theBG meter 10. Additionally, the pump 50 may send its clock time to the BGmeter 10, and the BG meter 10 may use the pump's clock time to reset theBG meter's clock time if the devices' clock times do not correspond withone another. Further, if the meter 10 does not receive an ACK responsefrom the pump 50, the meter 10 may attempt to retransmit thecommunication to the pump 50, either immediately or at a later time.

When the pump 50 receives a command packet from the BG meter 10, theprocessor 64 will send a data packet through the ASIC 84, commanding theRF receiver 80 to remain on full-time for a specified number of minutes,to receive other command packets or an information packet. The RFreceiver 80 may return to power cycling after the information packet hasbeen received, a certain period of time after receiving a BG measurementcommand (in the event that the anticipated information packet does notarrive), a certain period of time after receiving a bolus command, orafter-the battery in the pump 50 has been removed and replaced.

The pump RF PIC 82 remains in receive mode unless it has received acommand to send from the processor 64, in which case it shall switch totransmit mode until the transmission is complete. Once the data has beentransmitted, the pump RF PIC 82 automatically switches back to receivemode.

While the description above refers to particular embodiments of thepresent invention, it will be understood that many modifications may bemade without departing from the spirit thereof. The accompanying claimsare intended to cover such modifications as would fall within the truescope and spirit of the present invention.

The presently disclosed embodiments are therefore to be considered inall respects as illustrative and not restrictive, the scope of theinvention being indicated by the appended claims, rather than theforegoing description, and all changes which come within the meaning andrange of equivalency of the claims are therefore intended to be embracedtherein.

What is claimed is:
 1. An infusion system for infusing insulin into abody of a user, the infusion system comprising: a sensing deviceincluding: a sensor configured to continuously measure glucose levels inthe user; a sensing device processor coupled to the sensor andconfigured to process sensor values indicative of the glucose levels inthe user measured by the sensor; and a sensing device transmittercoupled to the sensing device processor and configured to transmit acommunication including the sensor values indicative of the glucoselevels in the user measured by the sensor; an external hand-heldcharacteristic determining device including: a determining devicehousing configured to be carried by the user; a receptacle coupled tothe determining device housing and configured to receive and test ablood sample from the user to obtain a blood glucose measurement; adetermining device processor contained in the determining device housingand coupled to the receptacle and configured to process the obtainedblood glucose measurement; and a determining device transmittercontained in the determining device housing and coupled to thedetermining device processor and configured to transmit a communicationincluding the obtained blood glucose measurement; and an infusion deviceincluding: an infusion device housing configured to be carried by auser; a drive mechanism contained in the infusion device housing andoperatively coupled with a reservoir containing insulin for infusing theinsulin into the body of the user; an infusion device receiver containedin the infusion device housing and configured to receive thecommunication from the sensing device transmitter and the communicationfrom the determining device transmitter; an infusion device processorcontained in the infusion device housing and coupled to the infusiondevice receiver and configured to process the sensor values receivedfrom the sensing device transmitter and the obtained blood glucosemeasurement received from the determining device transmitter; aninfusion device indicator coupled to the infusion device processor andconfigured to indicate the sensor values and the blood glucosemeasurement; and a bolus estimator used in conjunction with the infusiondevice processor for calculating an estimated amount of insulin to beinfused into the body of the user based upon the obtained blood glucosemeasurement received from the determining device transmitter and atarget blood glucose level for the user, wherein the infusion deviceprocessor determines an amount of time that has elapsed since theobtained glucose measurement was received from the determining devicetransmitter, and prevents the bolus estimator from calculating theestimated amount of insulin to be infused based upon the obtained bloodglucose measurement if the elapsed amount of time exceeds apredetermined amount of time, and causes the bolus estimator tocalculate the estimated amount of insulin to be infused based upon theobtained blood glucose measurement if the elapsed amount of time doesnot exceed the predetermined amount of time, and wherein the infusiondevice indicator further indicates when the estimated amount of insulinto be infused has been calculated.
 2. The infusion system according toclaim 1, wherein the sensing device transmitter continuously transmitsthe sensor values to the infusion device receiver.
 3. The infusionsystem according to claim 1, wherein the sensing device processor isfurther configured to calibrate the sensor values, and the sensingdevice transmitter transmits the calibrated sensor values to theinfusion device receiver.
 4. The infusion system according to claim 3,wherein the sensing device further includes a sensing device receivercoupled to the sensing device processor and configured to receive saidcommunication including the obtained blood glucose measurement from thedetermining device transmitter, and the sensing device processor isfurther configured to calibrate the sensor values based on the obtainedblood glucose measurement received from the determining devicetransmitter.
 5. The infusion system according to claim 1, wherein thesensing device transmitter transmits the communication including thesensor values to the infusion device receiver using wirelesscommunication.
 6. The infusion system according to claim 1, wherein theinfusion device receiver receives uncalibrated sensor values from thesensing device transmitter, and the infusion device processor is furtherconfigured to calibrate the received sensor values.
 7. The infusionsystem according to claim 6, wherein the infusion device processor isconfigured to calibrate the received sensor values based on the obtainedblood glucose measurement received from the determining devicetransmitter.
 8. The infusion system according to claim 6, wherein theinfusion device indicator is configured to display the calibrated sensorvalues.
 9. The infusion system according to claim 8, wherein theinfusion device indicator is configured to display the calibrated sensorvalues in response to input from the user.
 10. The infusion systemaccording to claim 1, wherein the infusion device indicator isconfigured to provide at least one of a visual indication, an audibleindication, or a tactile indication, to indicate when the sensor valuesare below or above predetermined levels.
 11. The infusion systemaccording to claim 1, wherein the infusion device is configured toautomatically contact an emergency response system if the sensor valuesare below or above predetermined levels.
 12. The infusion systemaccording to claim 11, wherein the infusion device is configured totransmit a global positioning signal to the emergency response system.13. The infusion system according to claim 1, wherein the characteristicdetermining device is a blood glucose meter.
 14. The infusion systemaccording to claim 1, wherein the determining device transmittertransmits the communication including the obtained blood glucosemeasurement to the infusion device receiver using wirelesscommunication.
 15. The infusion system according to claim 1, wherein thedetermining device processor has identification information, and whereinthe communication transmitted from the determining device transmitter tothe infusion device receiver further includes the identificationinformation of the determining device processor such that the infusiondevice is capable of deciding whether to accept the communication fromthe determining device transmitter.
 16. The infusion system according toclaim 15, wherein the identification information of the determiningdevice processor is unique.
 17. The infusion system according to claim1, wherein the infusion device processor has identification information,and wherein the communication transmitted from the determining devicetransmitter to the infusion device receiver further includes theidentification information of the infusion device processor such thatthe infusion device is capable of deciding whether to accept thecommunication from the determining device transmitter.
 18. The infusionsystem according to claim 17, wherein the identification information ofthe infusion device processor is unique.
 19. The infusion systemaccording to claim 1, wherein the sensing device processor hasidentification information, and wherein the communication transmittedfrom the sensing device transmitter to the infusion device receiverfurther includes the identification information of the sensing deviceprocessor such that the infusion device is capable of deciding whetherto accept the communication from the sensing device transmitter.
 20. Theinfusion system according to claim 19, wherein the identificationinformation of the sensing device processor is unique.
 21. The infusionsystem according to claim 1, wherein the infusion device processor hasidentification information, and wherein the communication transmittedfrom the sensing device transmitter to the infusion device receiverfurther includes the identification information of the infusion deviceprocessor such that the infusion device is capable of deciding whetherto accept the communication from the sensing device transmitter.
 22. Theinfusion system according to claim 21, wherein the identificationinformation of the infusion device processor is unique.
 23. The infusionsystem according to claim 1, wherein the infusion device furtherincludes a memory for storing data including the sensor values receivedfrom the sensing device and the obtained blood glucose measurementreceived from the characteristic determining device.
 24. The infusionsystem according to claim 23, wherein the data stored in the memory ofthe infusion device is downloaded from the infusion device to acomputer.
 25. The infusion system according to claim 24, wherein theinfusion device further includes an infusion device transmitter fortransmitting the data to be downloaded from the infusion device to thecomputer.
 26. The infusion system according to claim 25, wherein theinfusion device transmitter is configured to transmit the data to bedownloaded from the infusion device to the computer automatically atpredetermined times.
 27. The infusion system according to claim 25,wherein the infusion device receiver is configured to receive a signalfrom the computer, and the infusion device transmitter is configured totransmit the data to be downloaded from the infusion device to thecomputer automatically in response to the signal received from thecomputer.
 28. The infusion system according to claim 25, wherein thecharacteristic determining device further includes a determining devicereceiver configured to receive the data to be downloaded from theinfusion device transmitter to the computer, and the determining devicetransmitter is configured to transmit the received data to be downloadedto the computer.
 29. The infusion system according to claim 1, whereinthe sensing device transmitter is configured to transmit data to bedownloaded from the sensing device, wherein the infusion device furtherincludes an infusion device transmitter configured to transmit data tobe downloaded from the infusion device, and wherein the characteristicdetermining device further includes: a determining device receiverconfigured to receive the data to be downloaded from the sensing devicetransmitter and the infusion device transmitter; and a memory forstoring the data received from the sensing device and the infusiondevice.
 30. The infusion system according to claim 29, wherein the datastored in the memory of the characteristic determining device isdownloaded from the characteristic determining device to a computer. 31.The infusion system according to claim 30, wherein the determiningdevice transmitter is configured to transmit the data to be downloadedfrom the characteristic determining device to the computer.
 32. Theinfusion system according to claim 31, wherein the determining devicetransmitter is configured to transmit the data to be downloaded from thecharacteristic determining device to the computer automatically atpredetermined times.
 33. The infusion system according to claim 31,wherein the determining device receiver is configured to receive asignal from the computer, and the determining device transmitter isconfigured to transmit the data to be downloaded from the characteristicdetermining device to the computer automatically in response to thesignal received from the computer.
 34. The infusion system according toclaim 1, wherein the infusion device receiver uses one of radiofrequency, infrared, Bluetooth, and spread spectrum communication.